Libyan oil output has neared 1.1mn b/d on several occasions since the start of 2018. It averaged 1.06mn b/d in February, the highest figure since mid-2013. But ongoing political, economic and security challenges mean gains are fragile: witness ongoing outages at the remote fields in Libya’s desert southwest that have provided a third of the country’s output in recent months.

Libyan production has increased every quarter since the re-opening of key fields in late 2016 (see...